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1 Power electronics essentially deals with control of a.c. power at
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When a UJT is turned ON, the resistance between emitter terminal and lower base terminal
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As compared to oscillators, an inverter provides
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In a three phase half wave rectifier, each diode conducts for a duration of
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The ward-leonard system is used for controlling the speed of
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In single-phase full-wave controlled bridge rectifier, minimum output voltage is obtained at conduction angle and maximum at conduction angle
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The VI characteristics of UJT is
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Chopper control for DC motor provides variation in
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In a thyristor, ?dt protection is achieved through the use of
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A resistor connected across the gate and cathode of a thyristor increases its
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In series connected thyrstors
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Thyrisor A has rated gate carrent of 2 A while thyristor B has rated gate current of 200 mA. Then
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A single phase halfwave controlled rectifier has 400 sin 314 t volts as the input voltage and resistor R as the load. For firing angle of 600 for the SCR, the average output voltage in volts is
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The Doppler frequency is large if
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Radar range primarily depends upon
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The resolution of a pulsed radar can be improved by
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A simple CW radar does not give range information because